Question

3x – y = 28
3x + y = 14

Answer 1

Explanation:

3x=28+y

x=28+y÷3

then puttingx=28+y÷3

3x=14+y

3(28+y÷3)+y=14

84+3y+3y=42

3y+3y=42-84

y=-42÷6

y=7

so putting y=-7

3x-y=28

3x-7=38

x=38+7÷3

x=15